Treesearch

The Sierra Nevada is one of the most striking features of the state of California, extending from the southern Cascade Mountains in the north to the Tehachapi Mountains and Mojave Desert 620 km (435 mi) to the south (Map14.1). The Central Valley forms the western boundary of the Sierra Nevada bioregion, and the Great Basin is on the east. The bioregion includes the central mountains and foothills of the Sierra Nevada Section and the Sierra Nevada Foothills Section of Miles and Goudey (1997). The area of the bioregion is 69,560 km2 (26,442 mi2), approximately 17% of the state. Significant...

Oak woodlands are dependent on frequent fire to maintain the low stem density and diverse understories that typify these ecosystems. Without this recurrent disturbance, fire-sensitive conifer competitors encroach on oaks, reducing their vigor, and diminishing habitat quality. In fire-excluded oak woodlands, stand-replacing wildfire can trigger shifts in canopy dominance from seed-generated conifers to oaks, which are capable of vigorous sprouting following topkill. We examined the occurrence and sprouting dynamics of California black oak (Quercus kelloggiiNewb.) following repeated wildfires...

Veratrum woodii, a long-lived herbaceous perennial species, has a fragmented distribution with populations scattered in the southeastern and lower midwestern USA. In Georgia, the species has a protection status of rare. This preliminary study focused on verifying historic and/or unvouchered populations in Georgia and characterizing variation and genetic structure within and among all populations in the state. We analyzed AFLP (amplified fragment length polymorphism) data as dominantly inherited markers for 16 populations sampled from Georgia, Florida, and Missouri. Our results suggest that...

Barred owls (Strix varia) have reached high densities within the range of the northern spotted owl (S. occidentalis caurina) and are rapidly increasing in number within the range of the California spotted owl (S. o. occidentalis). Encroaching populations of barred owls pose a significant competitive threat to the viability of both spotted owl subspecies in California. In response, the Director of the California Department of Fish and Wildlife (CDFW) convened the California Barred Owl Science Team (BOST) to identify and address the threat posed by barred owls to spotted owls in California....

In 2009, the U.S. Congress designated Fossil Creek as a wild and scenic river (WSR), making it one of 209 rivers across 40 states and Puerto Rico with such a designation.1 It became a component of the National Wild and Scenic Rivers System through the Omnibus Public Lands Management Act in 2009 (Public Law 111-11). This designation amended the 1968 Wild and Scenic Rivers Act (WSRA) (Public Law 90-542), which states: “It is hereby declared to be the policy of the United States that certain selected rivers of the Nation which, with their immediate environments, possess outstandingly remarkabl...

This draft environmental impact statement (DEIS) documents the environmental effects analysis of six alternatives (including a “no action” alternative) that were developed for the draft Comprehensive River Management Plan (CRMP) for the Fossil Creek Wild and Scenic River. To meet the requirements of the Wild and Scenic Rivers Act, this project proposes a CRMP that formally designates the boundaries of the Fossil Creek Wild and Scenic River; describes Fossil Creek’s river values (free flow, water quality, and outstandingly remarkable values); addresses user capacities; provides programmatic...

Background: Crown fires are often intense and fast spreading and hence can have serious impacts on soil, vegetation, and wildlife habitats. Fire managers try to prevent the initiation and spread of crown fires in forested landscapes through fuel management. The minimum fuel conditions necessary to initiate and propagate crown fires are known to be strongly influenced by four stand structural variables: surface fuel load (SFL), fuel strata gap (FSG), canopy base height (CBH), and canopy bulk density (CBD). However, there is often a lack of quantitative data about these variables, especially...

This report focuses on the dynamic geologic processes that affect a travertine system within the Fossil Creek Wild and Scenic River (WSR) corridor, and the geologic hazards and mineral potential within the larger watersheds to assist in the establishment of management directions and site-specific improvements for protecting and enhancing river values of Fossil Creek. The National Wild and Scenic Rivers Act created by Congress in 1968 is notable for protecting the special character of designated rivers, and identifying appropriate use and development that does not adversely affect those...

The use of 50% concentration and 10% concentration hydrogen peroxide were evaluated for chemical and mechanical pulp bleach plants at storage and at point of use. Several dangerous occurrences have been documented when the supply of 50% peroxide going into the pulping process was not stopped during a process failure. Startup conditions and leaking block valves during maintenance outages have also contributed to explosions. Although hazardous events have occurred, 50% peroxide can be stored safely with proper precautions and engineering controls. For point of use in a chemical bleach plant,...

Expanding the footprint of natural fire has been proposed as one potential solution to increase the pace of forest restoration programs in fire-adapted landscapes of the western USA. However, studies that examine the long-term socio-ecological trade-offs of expanding natural fire to reduce wildfire risk and create fire resilient landscapes are lacking. We used the model Envision to examine the outcomes that might result from increased area burned by what we call “restoration” wildfire in a landscape where the ecological benefits of wildfire are known, but the need to suppress high-risk...